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Biomedical subjects

R Höfer

Publications and source records attributed to R Höfer.

At least 19 recordsLinked to original sources
PubMed1990

[Prevention of thromboembolism in para-articular femoral fractures of the hip--results of a prospective randomized study of heparin-DHE and ASS-DHE].

The effectiveness of prophylaxis of thromboembolism either by acetyl-salicylic-acid (ASA) 0.5 g + dihydroergotamin (DHE) 2.5 mg three times a day or by Heparin 5000 IU + 0.5 mg DHE (HDHE) three times a day was compared in 404 patients, elder than 55 years, with fractures close by the hip joint. Effectiveness was proved daily clinical controls, perfusion scintigraphy on the day after admission, the fourth postoperative day and the day before discharge and by autopsy of the died patients. Clinical manifest thrombosis were seen on the operated legs in the HDHE-group in 7.6% of the patients, in ASA-DHE-group in 15.6%, on the not operated leg under prophylaxis by HDHE in 3.8%, by ASA-DHE in 4.1% of the patients. Increased postoperative bleeding could be found under HDHE in 16.1% of the patients, under ASA-DHE in 9.3% of the patients, wound haematoma in 9.5% under HDHE and in 5.7% of the patients of the ASA-DHE-group. Superficial wound infections occurred under HDHE in 8.1%, under ASA-DHE in 5.7% of the patients, deep infections under HDHE in 0.5% and under ASA-DHE in 1.6% of the patients. Gastrointestinal bleeding under HDHE in 0.5% of the cases and under ASA-DHE in 3.1% of the cases. Prophylaxis had to be discharged in 7.6% of the patients of the HDHE-group and of 19.7% of the ASA-DHE-group. Pathologic perfusion scars should be found in 54.0% of the patients of the HDHE-group and in 54.9% of the ASA-DHE-group. Pulmonal perfusion became worse despite of prophylaxis by HDHE in 15.6% of the cases and despite prophylaxis with ASA-DHE in 17.6%. Pulmonal perfusion became better under HDHE in 11.9% and under ASA-DHE in 12.4% of the cases. The mortality was 9.7%. Fatal thromboembolism occurred under HDHE in three patients (1.4%) and under ASA-DHE in three patients too (1.6%), after subcapital fractures in 0.5%, after pertrochanteric fractures in 2.1% and after subtrochanteric fractures in 6.25% of the patients without any significant difference between the two groups of prophylaxis. Fatal gastrointestinal bleeding had to be remarked in 1.0% of the patients of the HDHE-group and in 2.1% of the ASA-DHE-group, fatal infections in 0.5% of the patients of the HDHE-group and in 1.6% of the ASA-DHE-group. Fatal cardinal infarction could be seen under HDHE in 1.9% of the patients, under ASA-DHE no fatal cardial infarction occurred.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1989

[Loss of high-affinity prostacyclin binding sites in patients with Basedow's disease].

Prostacyclin (PGI2) mediates like TSH its cellular effects through the interaction with specific binding sites associated with the adenylate cyclase-cAMP-system. Binding of PGI2 and the generation of cAMP induced by PGI2 was evaluated in thyroid tissue obtained intraoperatively from euthyroid and hyperthyroid patients with diffuse normofollicular colloid struma. Transformation of the binding data according to Scatchard revealed heterogeneity of the PGI2 binding sites in the tissue of euthyroid patients: the high-affinity binding sites were calculated to be 0.68 +/- 0.18 pmol/mg protein (Ka = 16.2 +/- 9.1 nM) and the low-affinity binding sites to be 5.4 +/- 1.6 pmol/mg protein (Ka = 151 +/- 43.1 nM). In contrast, in the hyperthyroid patients the low-affinity binding sites were not demonstrable and the high-affinity sites were significantly (p less than 0.001) reduced (0.17 +/- 0.05 pmol/mg protein, Ka = 83.5 +/- 19.6 nM). The competition of the agonist for the PGI2 sites in hyperthyroid patients was significantly (p less than 0.005) diminished (IC-50-values: 0.98 +/- 3.1 vs 46.9 +/- 12.1 microM). PGI2 stimulated cAMP-production in a dose-dependent manner. However, the basal value was significantly lower also in the hyperthyroid patients (p less than 0.001). The evidence of reduced PGI2 sites as well as reduced PGI2-induced cAMP production in the thyroid gland of patients with Graves' disease may indicate an important role for PGI2 to play in the modulation of thyroid cell function.

Adult↗
PubMed1987

[Reflections on the therapeutic goal in Basedow hyperthyroidism].

The present state of knowledge of the patho-etiology of autoimmune-hyperthyroidism (Graves' disease) enables us to design a therapeutic strategy basing on causal events of the autoimmune disease and aiming at complete restoration, considering the pros and cons of conservative (antithyroid drug) and destructive (surgery and/or radioactive iodine) therapy. Summarizing the arguments it is stated that antithyroid drugs are the therapy of first choice in Graves' disease, there are, however, no parameters available to predict firmly relapse in hyperthyroid Graves' disease and to establish duration of antithyroid drug treatment. For patients with hyperthyroid Graves' disease recurring after long term antithyroid drug treatment ablation of the thyroid gland as target organ of the autoimmune disease is advocated; requirements for this decision are discussed.

Antithyroid Agents↗
PubMed1986

[Diagnosis of radionuclide uptake using a whole body counter].

Measurements of whole body radioactivity are performed at our department using a shadow shield whole body counter with automated gammaspectrum analysis. After the radioactive fall-out in Austria due to the reactor accident in Chernobyl the instrument has mainly been used for the assessment of the radiation level in the general population. Amongst the radionuclides incorporated 131-I and 137-Cs had the highest activities. The results of our measurements are summarized in two graphs. At present an increase of 137-Cs activity in the population is clearly observed.

Accidents↗
PubMed1986

[Limit values, the philosophy of establishing limit values].

Both determination and significance of radiation exposure limits are dependent on the respective situation. The simplest case is the determination of limits for direct effect of a clearly defined radiation dose upon organism, which occurs at doses above a value of about 25 rem. Determination and significance of a limiting value for the maximum permissible dose for radiation workers are also obvious; it indicates the calculated increase of risk and its value (5 rem/a) refers to the "tolerated risk" in other professions. An essentially different situation occurs if the radiation doses in question are far below 5 rem/a, as it is the case in consequence of the Chernobyl nuclear accident. In this case there is no opportunity of determining a relation between radiation dose and its effect in a scientific and objective way: the relation is postulated by extrapolation of the calculated values. There are two possible solutions: either determination of the limit as a certain fraction of the limiting value for professional exposure (as it has been practiced in France and Switzerland), or consideration of the ICRP recommendation to keep the limits "as low as reasonably achievable" with regard to social, economical and psychological factors. Austria has chosen this solution. Public information about origin and meaning of these limiting values is a necessary condition to avoid that a value above the limits is considered necessarily harmful.

Accidents↗
PubMed1986

Changes in biochemical parameters during complete thyroid hormone deficiency of short duration in athyreotic patients.

The effect of withdrawal of suppressive therapy with thyroid hormones (200 micrograms L-thyroxine/day) on serum biochemical profiles and blood cell counts were studied in ten athyreotic thyroid carcinoma patients. After 14 days off therapy, all patients but one were still clinically and biochemically euthyroid. Twenty-eight days without thyroid hormones resulted in severe clinical and biochemical (TT4, TSH) hypothyroidism. At that time, the following parameters changed significantly: CPK activities increased (in five of ten patients above normal) as well as activities of SGOT, SGPT, and LDH (means and s.d.s within the respective normal ranges). Total cholesterol and triglycerides increased within the normal range. There were minimal but significant increases of serum creatinine and of mean corpuscular volume of erythrocytes as well as decreases of serum sodium and calcium. Our study underlines the importance of further investigation if pathologic biochemical or hematologic parameters are obtained in athyreotic patients after 4 wk withdrawal of thyroid hormone therapy.

Adult↗
PubMed1984

Detection of aneurysms by gamma-camera imaging after injection of autologous labelled platelets.

Autologous platelet labelling was used to calculate platelet half-life in 860 patients with symptoms of coronary heart disease and/or peripheral vascular disease. Abnormal platelet deposition indicating an abdominal aortic aneurysm was found in 21 by gamma-camera imaging after reinjection of autologous indium-111 labelled platelets. Aneurysms detected by imaging were confirmed by angiography, computer tomography, and at subsequent surgery.

Adult↗
PubMed1984

Decreased insulin receptor binding in hyperthyroidism.

The binding of 125I-insulin to insulin receptors on circulating mononuclear leukocytes was studied in ten patients with hyperthyroidism and 20 euthyroid normal volunteers. The hyperthyroid patients demonstrated significantly elevated glucose levels following an oral glucose load, despite normal insulin secretion. The infusion of insulin resulted in a delayed hypoglycaemic effect in the hyperthyroid patients; however, the inhibition of the endogenous insulin secretion as indicated by suppression of C-peptide levels was not different from euthyroid control subjects. Insulin binding to monocytes was significantly decreased in the hyperthyroid patients. Scatchard analysis of binding data indicates that a decrease of receptor number rather than receptor affinity seems to be the cause of the lowered insulin binding in hyperthyroid patients with diffuse toxic goitre. The findings of decreased insulin receptor number, mild degree of glucose intolerance despite normal insulin secretion and the delayed hypoglycaemic effect following insulin infusion suggest that peripheral insulin resistance could be involved in the highly complex pathophysiology of glucose intolerance in hyperthyroidism.

Adult↗
PubMed1984

[Technic of radioactive labeling of autologous human thrombocytes using 111-indium-oxine and 111-indium-oxine-sulfate and their clinical use].

Using 111indium oxine and 111indium oxine sulphate as platelet labels, maximal labelling efficiency can be achieved already after 3 minutes at an incubation temperature of 37 degrees C. Mean labelling efficiency values of about 90% are reached at a platelet count of greater than 10(9) platelets/ml, but the labelling efficiency is satisfactory also at a rather low platelet count of about 10(6) platelets/ml (71% on average). Platelet labelling with these tracers allows the calculation of platelet half-life in vivo, and gamma-camera imaging of platelet aggregates in thrombosis and renal transplant rejection as well. In the present study, the platelet half-life is significantly shortened in patients with coronary heart disease (n = 15), peripheral vascular disease (n = 13) and primary hyperlipoproteinaemia (n = 32) in comparison with 106 controls. No age dependence of platelet half-life was found in the different groups of patients whereas in the control group, a significant negative correlation between age and platelet half-life was observed.

Adult↗
PubMed1984

A simple and safe technique for sterile autologous platelet labelling using "Monovette" vials.

A simple technique of autologous platelet labelling is described, which allows labelling within 40 min, and has the advantage of low costs, as no laminar air flow is required. Blood (16 ml) was withdrawn into 4 ml ACD, 500 ng prostacyclin was added. After 10 min sedimentation the vials were centrifuged for 5 min at 150 g. The plateletrich plasma in the supernatant was centrifuged at 500 g for 10 min to obtain a platelet pellet. The platelet-poor plasma was preserved in a sterile syringe and the platelet pellet was resuspended in 1 ml tyrode buffer. The cell suspension was labelled at 37 degrees C for 5 min with 100 muCi 111In-oxine sulphate and reinjected after dilution with the plasma. Mean labelling efficiency was 90% +/- 3%, mean recovery 2 h after reinjection 76% +/- 3% (mean +/- SD).

Blood Platelets↗
PubMed1984

Right ventricular performance in chronic air flow obstruction.

Right ventricular pump performances were assessed in 14 patients with chronic obstructive pulmonary disease by means of radionuclide angiocardiography using krypton-81m as a tracer. Right ventricular ejection fraction (RVEF) was significantly lower in the patients than in normal volunteers. Additionally there was a striking difference in RVEF between patients with normal pulmonary artery pressure (PAP) and those with pathologically elevated PAP. A linear negative correlation between RVEF and mean PAP could be demonstrated. From this data we suggest that radionuclide angiocardiography using krypton-81m allows non invasive assessment of right heart afterload and thus indirectly PAP.

Adult↗
PubMed1984

[Thyroid functional parameters during anti-arrhythmia therapy with amiodarone].

Thyroid function was investigated in 41 patients on chronic treatment with amiodarone. 27% of the patients had elevated total thyroxine levels together with elevated free thyroxine levels. Thyrotropin (TSH) secretion was completely suppressed in 15% of the patients. Elevated free or total thyroxine levels were frequently observed together with normal TSH secretion, although 5 of the 6 patients with suppressed TSH had markedly elevated levels. Triiodothyronine (T3) levels were low normal or below the normal range in all patients but one. This was the only patient who apparently developed amiodarone-induced hyperthyroidism. The clinical symptoms of this patient were equivocal. Thyroid function parameters including T3 levels returned to normal only 3 months after withdrawal of the drug. The patient did not need any thyrostatic treatment. The duration of treatment with amiodarone did not influence thyroid hormone concentrations, although there was an insignificant trend of increasing total thyroxine levels after a year of treatment. There was, moreover, no significant influence of the dose (200-500 mg orally/day) of amiodarone on thyroid hormone levels. Our results show that the usual screening parameters of thyroid function, namely total and free thyroxine serum concentrations, are not reliable in patients on chronic amiodarone treatment. The incidence of amiodarone-induced hypothyroidism was 2.4%. We did not observe an amiodarone-induced hypothyroidism, although there was one patient with increased TSH levels but normal T3 and thyroxine levels.

Adolescent↗
PubMed1983

[Human calcitonin in the treatment of symptomatic Paget's disease].

We evaluated the effect of a 6 months trial with synthetic human calcitonin in 10 symptomatic patients with polyosseous Paget's disease of bone. All patients reported a distinct clinical improvement which correlated with a significant decrease of alkaline phosphatase in the plasma and hydroxyproline and calcium excretion in the urine. Though no changes in skeletal x-rays were observed, the bone lesions showed a significant decrease of activity in tho bone scintigrams. Histologically there was a marked decrease of bone turn-over calcitonin therapy. No patient revealed the formation of autoantibodies against exogenous calcitonin after treatment.

Aged↗